To address whether B cell deficiency alter the atherogenic response to castration in male mice, we studied μMT and genotype control mice on an atherosclerosis-prone Apoe-/- background that were castrated or sham-operated before puberty (at 3 weeks of age) and fed a high-fat diet between 8 and 16 weeks of age to accelerate atherosclerosis development. This evidence concerns the gene APOE and B cell deficiency.